According to the prior art the process of arranging similar gas filters on recipients consists of two separate phases. In a first phase the gas filters per se are produced and in a second phase the produced gas filter is then arranged on a recipient.
Through the use of two different production lines and machines for manufacturing the filters on the one hand and placing the filters on the other, the process of arranging such a gas filter on a recipient becomes complicated and time-consuming.
U.S. Pat. No. 4,318,406 discloses a venting filter for ostomy bags. The venting filter consists of three layers, wherein the central layer comprises a carbon cloth situated between two air-permeable material layers. The three layers are secured to each other by means of a circular weld. Further described are two different embodiments wherein the three-layer filter is secured to the ostomy bag by means of a fourth layer. According to the first embodiment the fourth layer is a material layer with a larger periphery than the periphery of the three-layer filter, wherein the fourth layer is secured against the ostomy bag over the three-layer filter by means of an adhesive layer or weld at the periphery of the fourth layer. According to the second embodiment the fourth layer is an adhesive layer situated between the ostomy bag and the three-layer filter. The operation of the three-layer filter is based on the presence of activated carbon in the carbon cloth.
U.S. Pat. No. 4,120,715 discloses a method for manufacturing the venting filters described in U.S. Pat. No. 4,318,406.